vmstat(1M) System Administration Commands vmstat(1M)NAMEvmstat - report virtual memory statistics
SYNOPSISvmstat [-cipqsS] [disks] [ interval [count]]
DESCRIPTIONvmstat reports virtual memory statistics regarding kernel thread, vir‐
tual memory, disk, trap, and CPU activity.
On MP (multi-processor) systems, vmstat averages the number of CPUs
into the output. For per-processor statistics, see mpstat(1M).
vmstat only supports statistics for certain devices. For more general
system statistics, use sar(1), iostat(1M), or sar(1M).
Without options, vmstat displays a one-line summary of the virtual mem‐
ory activity since the system was booted.
During execution of the kernel status command, the state of the system
can change. If relevant, a state change message is included in the
vmstat output, in one of the following forms:
<<device added: sd0>>
<<device removed: sd0>>
<<processors added: 1, 3>>
<<processors removed: 1, 3>>
See System Administration Guide: Advanced Administration for device
naming conventions for disks.
OPTIONS
The following options are supported:
-c Report cache flushing statistics. This option is obsolete, and
no longer meaningful. This option might be removed in a
future version of Solaris.
-i Report the number of interrupts per device. count and interval
does not apply to the -i option.
-p Report paging activity in details. This option will display
the following, respectively:
epi Executable page-ins.
epo Executable page-outs.
epf Executable page-frees.
api Anonymous page-ins.
apo Anonymous page-outs.
apf Anonymous page-frees.
fpi File system page-ins.
fpo File system page-outs.
fpf File system page-frees.
When executed in a zone and if the pools facility is active,
all of the above only report actitivity on the processors in
the processor set of the zone's pool.
-q Suppress messages related to state changes.
-s Display the total number of various system events since boot.
count and interval does not apply to the -s option.
-S Report on swapping rather than paging activity. This option
will change two fields in vmstat's ``paging'' display: rather
than the ``re'' and ``mf'' fields, vmstat will report ``si''
(swap-ins) and ``so'' (swap-outs).
OPERANDS
The following operands are supported:
count Specifies the number of times that the statistics are
repeated. count does not apply to the -i and -s
options.
disks Specifies which disks are to be given priority in the
output (only four disks fit on a line). Common disk
names are id, sd, xd, or xy, followed by a number (for
example, sd2, xd0, and so forth).
interval Specifies the last number of seconds over which vmstat
summarizes activity. This number of seconds repeats
forever. interval does not apply to the -i and -s
options.
EXAMPLES
Example 1: Using vmstat
The following command displays a summary of what the system is doing
every five seconds.
example% vmstat 5
kthr memory page disk faults cpu
r b w swap free re mf pi p fr de sr s0 s1 s2 s3 in sy cs us sy id
0 0 0 11456 4120 1 41 19 1 3 0 2 0 4 0 0 48 112 130 4 14 82
0 0 1 10132 4280 0 4 44 0 0 0 0 0 23 0 0 211 230 144 3 35 62
0 0 1 10132 4616 0 0 20 0 0 0 0 0 19 0 0 150 172 146 3 33 64
0 0 1 10132 5292 0 0 9 0 0 0 0 0 21 0 0 165 105 130 1 21 78
1 1 1 10132 5496 0 0 5 0 0 0 0 0 23 0 0 183 92 134 1 20 79
1 0 1 10132 5564 0 0 25 0 0 0 0 0 18 0 0 131 231 116 4 34 62
1 0 1 10124 5412 0 0 37 0 0 0 0 0 22 0 0 166 179 118 1 33 67
1 0 1 10124 5236 0 0 24 0 0 0 0 0 14 0 0 109 243 113 4 56 39
^C
example%
The fields of vmstat's display are
kthr Report the number of kernel threads in each of the
three following states:
r the number of kernel threads in run queue
b the number of blocked kernel threads that are
waiting for resources I/O, paging, and so
forth
w the number of swapped out lightweight pro‐
cesses (LWPs) that are waiting for processing
resources to finish.
memory Report on usage of virtual and real memory.
swap available swap space (Kbytes)
free size of the free list (Kbytes)
page Report information about page faults and paging activ‐
ity. The information on each of the following activi‐
ties is given in units per second.
re page reclaims — but see the -S option for how
this field is modified.
mf minor faults — but see the -S option for how
this field is modified.
pi kilobytes paged in
po kilobytes paged out
fr kilobytes freed
de anticipated short-term memory shortfall
(Kbytes)
sr pages scanned by clock algorithm
When executed in a zone and if the pools facility is
active, all of the above (except for "de") only report
activity on the processors in the processor set of the
zone's pool.
disk Report the number of disk operations per second. There
are slots for up to four disks, labeled with a single
letter and number. The letter indicates the type of
disk (s = SCSI, i = IPI, and so forth); the number is
the logical unit number.
faults Report the trap/interrupt rates (per second).
in interrupts
sy system calls
cs CPU context switches
When executed in a zone and if the pools facility is
active, all of the above only report actitivity on the
processors in the processor set of the zone's pool.
cpu Give a breakdown of percentage usage of CPU time. On MP
systems, this is an average across all processors.
us user time
sy system time
id idle time
When executed in a zone and if the pools facility is
active, all of the above only report actitivity on the
processors in the processor set of the zone's pool.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Availability │SUNWcsu │
├─────────────────────────────┼─────────────────────────────┤
│Interface Stability │See below. │
└─────────────────────────────┴─────────────────────────────┘
Invocation is evolving. Human readable output is unstable.
SEE ALSOsar(1), iostat(1M), mpstat(1M), sar(1M), attributes(5)
System Administration Guide: Basic Administration
System Administration Guide: Advanced Administration
NOTES
The sum of CPU utilization might vary slightly from 100 because of
rounding errors in the production of a percentage figure.
The -c option (Report cache flushing statistics) is not supported in
this release.
SunOS 5.10 20 Dec 2004 vmstat(1M)